Biomaterial Database

Isolation and characterization of mitochondrial DNA from Chlamydomonas reinhardtii. 1978

R Ryan, and D Grant, and K S Chiang, and H Swift

Mitochondrial DNA (mtDNA) has been isolated from a mitochondrial pellet of Chlamydomonas reinhardtii. The mtDNA has a buoyant density of 1.706 g/ml in CsCl, a melting temperature of 87.9 degrees in standard saline citrate, and a nucleoside composition of 47.5% deoxyguanidine plus deoxycytidine with no odd nucleosides. Thermal denaturation and renaturation studies have shown that (i) mtDNA contains no extensive intramolecular heterogeneity nor significant base bias between the complementary polynucleotide chains and (ii) mtDNA renatures as a single homogeneous class with a kinetic complexity of 9.78 X 10(6) daltons. Although rare (less than or equal to 1%), both open and supercoiled circular mtDNA molecules have been observed in the electron microscope. Contour lengths of linear and open and closed circular molecules are all within the range of 4.0-5.4 micron with a mean of 4.67 +/- 0.30 micron. This size is similar to that of animal mtDNA but approximately 1/8 that of the higher plant mtDNAs. The magnitude of mtDNA reiteration in C. reinhardtii is estimated to be of the same order as that of chloroplast DNA.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009691	Nucleic Acid Denaturation	Disruption of the secondary structure of nucleic acids by heat, extreme pH or chemical treatment. Double strand DNA is "melted" by dissociation of the non-covalent hydrogen bonds and hydrophobic interactions. Denatured DNA appears to be a single-stranded flexible structure. The effects of denaturation on RNA are similar though less pronounced and largely reversible.	DNA Denaturation,DNA Melting,RNA Denaturation,Acid Denaturation, Nucleic,Denaturation, DNA,Denaturation, Nucleic Acid,Denaturation, RNA,Nucleic Acid Denaturations
D009695	Nucleic Acid Renaturation	The reformation of all, or part of, the native conformation of a nucleic acid molecule after the molecule has undergone denaturation.	Acid Renaturation, Nucleic,Acid Renaturations, Nucleic,Nucleic Acid Renaturations,Renaturation, Nucleic Acid,Renaturations, Nucleic Acid
D009705	Nucleosides	Purine or pyrimidine bases attached to a ribose or deoxyribose. (From King & Stansfield, A Dictionary of Genetics, 4th ed)	Nucleoside,Nucleoside Analog,Nucleoside Analogs,Analog, Nucleoside,Analogs, Nucleoside
D002500	Centrifugation, Isopycnic	A technique used to separate particles according to their densities in a continuous density gradient. The sample is usually mixed with a solution of known gradient materials and subjected to centrifugation. Each particle sediments to the position at which the gradient density is equal to its own. The range of the density gradient is usually greater than that of the sample particles. It is used in purifying biological materials such as proteins, nucleic acids, organelles, and cell types.	Isopycnic Centrifugation
D002696	Chlamydomonas	A genus GREEN ALGAE in the order VOLVOCIDA. It consists of solitary biflagellated organisms common in fresh water and damp soil.	Chlamydomona
D004270	DNA, Circular	Any of the covalently closed DNA molecules found in bacteria, many viruses, mitochondria, plastids, and plasmids. Small, polydisperse circular DNA's have also been observed in a number of eukaryotic organisms and are suggested to have homology with chromosomal DNA and the capacity to be inserted into, and excised from, chromosomal DNA. It is a fragment of DNA formed by a process of looping out and deletion, containing a constant region of the mu heavy chain and the 3'-part of the mu switch region. Circular DNA is a normal product of rearrangement among gene segments encoding the variable regions of immunoglobulin light and heavy chains, as well as the T-cell receptor. (Riger et al., Glossary of Genetics, 5th ed & Segen, Dictionary of Modern Medicine, 1992)	Circular DNA,Circular DNAs,DNAs, Circular
D004272	DNA, Mitochondrial	Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.	Mitochondrial DNA,mtDNA